Phil Mickelson plays a bunker shot on the third hole as his caddie Jim Mackay looks on during the Day Two Foursome Matches at the Muirfield Village Golf Club on October 4, 2013 in Dublin, Ohio. (Photo by Gregory Shamus/Getty Images) ORG XMIT: 171922653 ORIG FILE ID: 183106218 Gregory Shamus Getty Images

Jason Day lines up a putt with his caddie Colin Swatton. Gregory Shamus Getty Images